About Behavioral Finance

Behavioral Vulnerabilities:



About Prospect Theory: An Analysis of Decision under Risk

The theory distinguishes two phases in the choice process: an early phase of editing and a subsequent phase of evaluation; the editing phase consists of a preliminary analysis of the offered prospects, which often yields a simpler representation of theses prospects, whereas the edited prospects are evaluated in the second phase and the prospect of the highest value is chosen.

Outcomes which are obtained with certainty are overweighted relative to uncertain outcomes. Certainty increases the aversiveness of losses as well as the desirability of gains

In the positive domain, the certainty effect contributes to a risk averse preference for a sure gain over a larger gain that is merely probable; in the negative domain, the same effect leads to a risk seeking preference for a loss that is merely probable over a smaller loss that is certain (the overweighting of certainty favors risk aversion in the domain of gains and risk seeking in the domain of losses)

Value function: Reference point + Magnitude of the change. (vs final welfare states)

The value function is normally concave above the reference point and often convex below it, meaning, the marginal value of both gains and losses generally decreases with their magnitude.

Losses loom larger than gains; the aggravation that one experiences in losing a sum of money appears to be greater than the pleasure associated with gaining the same amount (i.e.: the value function for losses is steeper than the value function for gains).

Because people are limited in their ability to comprehend and evaluate extreme probabilities, highly unlikely events are either ignored or overweighted, and the difference between high probability and certainty is either neglected or exaggerated.

... which leads to perceive both insurance and lottery/gambling as atractive.

It is suggested that a person who has not made peace with his losses is likely to accept gambles that would be unacceptable to him otherwise (e.g.: Leeson at Barings Bank, Citron at Orange County)